City staff plan would reduce nitrates at wastewater plant

Published: Tuesday, September 10, 2013 at 5:21 p.m.

Last Modified: Tuesday, September 10, 2013 at 5:21 p.m.

If the Ocala City Council gives its approval, city staff will apply for a grant from the St. Johns River Water Management District to help modify one of the city's three sewer plants to reduce nitrates to meet advanced wastewater treatment standards.

At a City Council workshop meeting Tuesday, city Water and Sewer Director Jeff Halcomb said changes to the plant could reduce the nitrates that pollute local springs from Water Reclamation Facility No. 2 from about 31.5 milligrams per liter per day to 3 mg/l per day.

“We currently meet standards,” Halcomb said about the amount of nitrates being emitted.

However, to meet Florida Department of Environmental Protection's new Total Maximum Daily Load standards for nitrates being discharged, the treatment process at WRF No. 2 will have to be modified. To meet the standard, the nitrates would have to be reduced by 79 percent. What the city staff is proposing would reduce the load by 90 percent, to 3 mg/l per day and, thus, meet the FDEP's stricter advanced wastewater standards.

To do that, staff is proposing to extend three of the existing aeration basins by 28 feet and add one new aeration basin. The process they are suggesting currently is being used at WRF#3, so they are confident they can meet the lower levels at WRF#2.

“We have to build more tankage,” Ed Ernest, deputy city engineer, told the council. “We hope to save anywhere from $2 million to $3 million on cost by using the existing basins.”

The sewer plant, which is located at 4200 SE 24th St., was built in 1972. The plant was upgraded in 1992 to increase its capacity from 3 million gallons a day to the current 6.5 million gallons a day, Ernest said.

Darryl Muse, water and sewer utility services manager, told the council the project is estimated to cost $12 million.

If the council gives its blessing, the staff would apply to St. John's River Water Management District for a $3.8 million grant, with St. John's providing $1.9 million and FDEP giving $1.9 million. He said the project would have to be completed within two years.

The city would have to lay out the money for the project up front and would be reimbursed by St. John's.

Halcomb said the city would pay for the project out of the Water and Sewer Department's reserves.

“We are going to be able to do that, so we won't put the city into debt,” Halcomb said.

Muse said the project would enable the city to remove 600,000 pounds of nitrates coming out of the plant and keep it from going into springs.

Ernest said the city already had the plans and specifications completed and would like to go out to bid in January.

“That's the goal,” he said. “I am on track with this.”

Since the council cannot vote at workshop meetings, the request to apply for the grant likely will come to it for consideration at its Oct. 1 meeting.

<p>If the Ocala City Council gives its approval, city staff will apply for a grant from the St. Johns River Water Management District to help modify one of the city's three sewer plants to reduce nitrates to meet advanced wastewater treatment standards.</p><p>At a City Council workshop meeting Tuesday, city Water and Sewer Director Jeff Halcomb said changes to the plant could reduce the nitrates that pollute local springs from Water Reclamation Facility No. 2 from about 31.5 milligrams per liter per day to 3 mg/l per day.</p><p>“We currently meet standards,” Halcomb said about the amount of nitrates being emitted.</p><p>However, to meet Florida Department of Environmental Protection's new Total Maximum Daily Load standards for nitrates being discharged, the treatment process at WRF No. 2 will have to be modified. To meet the standard, the nitrates would have to be reduced by 79 percent. What the city staff is proposing would reduce the load by 90 percent, to 3 mg/l per day and, thus, meet the FDEP's stricter advanced wastewater standards.</p><p>To do that, staff is proposing to extend three of the existing aeration basins by 28 feet and add one new aeration basin. The process they are suggesting currently is being used at WRF#3, so they are confident they can meet the lower levels at WRF#2.</p><p>“We have to build more tankage,” Ed Ernest, deputy city engineer, told the council. “We hope to save anywhere from $2 million to $3 million on cost by using the existing basins.”</p><p>The sewer plant, which is located at 4200 SE 24th St., was built in 1972. The plant was upgraded in 1992 to increase its capacity from 3 million gallons a day to the current 6.5 million gallons a day, Ernest said.</p><p>Darryl Muse, water and sewer utility services manager, told the council the project is estimated to cost $12 million.</p><p>If the council gives its blessing, the staff would apply to St. John's River Water Management District for a $3.8 million grant, with St. John's providing $1.9 million and FDEP giving $1.9 million. He said the project would have to be completed within two years.</p><p>The city would have to lay out the money for the project up front and would be reimbursed by St. John's.</p><p>Halcomb said the city would pay for the project out of the Water and Sewer Department's reserves.</p><p>“We are going to be able to do that, so we won't put the city into debt,” Halcomb said.</p><p>Muse said the project would enable the city to remove 600,000 pounds of nitrates coming out of the plant and keep it from going into springs.</p><p>Ernest said the city already had the plans and specifications completed and would like to go out to bid in January.</p><p>“That's the goal,” he said. “I am on track with this.”</p><p>Since the council cannot vote at workshop meetings, the request to apply for the grant likely will come to it for consideration at its Oct. 1 meeting.</p>